Industrial yarn, fiber fabric and flexible anode plate made thereof

Abstract

The technical field of air pollutant control, in particular, relates to an aging-resistant flexible anode plate of a wet electrostatic precipitator required for coal-fired flue gas control in coal-fired power plants. The flexible anode plate is made of a fiber fabric, and the fiber fabric is knitted from an industrial yarn and an aramid skeleton. The industrial yarn is spun by plying and twisting industrial yarns made of conventional non-flame-retardant fiber materials and flame-retardant fiber materials with heat-resistant effects. Specifically, it is made by plying and twisting industrial polyester spun yarn and industrial nitrile chlorofiber spun yarn. A single industrial yarn contains 2-10 yarns, and the ratio of the number of industrial polyester spun yarn to the number of industrial nitrile chlorofiber spun yarn is 2:1-1:2. This fiber fabric is applied to the flexible anode plate, which realizes the unity of high-efficiency flame retardancy and long-term mechanical stability of the flexible anode plate, and eliminates the problem of rapid aging of the existing flame-retardant flexible anode plate.

Description

Technical Field

[0001] The invention belongs to the technical field of air pollutant treatment, and in particular relates to an industrial yarn and fiber fabric required for coal-fired flue gas treatment in a coal-fired power station, and a flexible anode plate made thereof. Background Art

[0002] Wet electrostatic precipitator (hereinafter referred to as "wet electrostatic precipitator") is a technical equipment specified in the "Technical Specification for Ultra-low Emission Flue Gas Treatment Engineering in Coal-fired Power Plants" (HJ 2053-2018). It can process wet saturated flue gas after wet desulfurization, and reduce the content of acid droplets and fine particles in the flue gas, so that the particulate matter in the outlet flue gas reaches "ultra-low" or even lower indicators. Its large-scale application has made due contributions to the coal-fired power generation industry. At the same time, wet electrostatic precipitator is also an important technical means to "win the battle to protect the blue sky" and promote the implementation of ultra-low emission transformation in non-electric industries such as steel. The dust collecting plate is the core component of wet electrostatic precipitator. According to the different plate materials, wet electrostatic precipitator can be divided into three major technical series: stainless steel plate, fiberglass plate, and flexible plate.

[0003] There is a high-voltage electric field inside the wet electrostatic precipitator during operation, and its safety cannot be ignored. The dust collecting plate is the core component of the wet electrostatic precipitator, which is used to realize the dust collection and flushing functions. Its own safety has a huge impact on the overall safety performance of the wet electrostatic precipitator. At present, patent CN112011879 B discloses a fiber fabric used as the dust collecting plate material of the wet electrostatic precipitator, which is made of flame-retardant polyester chips and spun into flame-retardant yarn, and the flame-retardant yarn is warped with flame-retardant grease, and then processed into fiber fabric. The fiber fabric is used to make the dust collecting anode of the wet electrostatic precipitator.

[0004] Flame retardant polyester chips are formed by combining phosphorus flame retardant materials (organic phosphates, etc.) with polyester (polyester molecules) at the molecular level. Phosphorus flame retardant materials include tricresyl phosphate, triphenyl phosphate, tri(xylene) phosphate, butylbenzene phosphate, propylbenzene phosphate, etc. The characteristics of phosphate esters are that they have the dual functions of flame retardancy and plasticization. Their characteristics are: less toxic and corrosive gases are generated than halogen flame retardants, less corrosiveness during processing and combustion, and have the effect of preventing re-ignition.

[0005] At present, phosphorus-based flame retardant materials are the mainstream flame retardants used in the production of flame-retardant fabrics. The existing flame-retardant flexible anode plates are made of phosphorus-based flame retardant materials (organic phosphates, etc.) that are copolymerized with polyester (polyester molecules) at the molecular level to form slices, which are then made through spinning, weaving, shaping and other processes. However, in actual engineering applications, it was found that wet electrostatic flexible plates with phosphorus-based flame retardant materials as effective flame retardants showed rapid aging when treating flue gas after desulfurization (about 50°C, polyacidic environment). The main manifestation is that the mechanical strength of the flexible fiber plates decreases rapidly, causing the plates to tear and break, which seriously affects the overall performance of the wet electrostatic precipitator. The reason is that organic phosphates are grafted copolymerized or blended to form slices for spinning, which is difficult to exist for a long time under acidic conditions of 50°C. Under acidic conditions of 50°C, both phosphates and polyester polyesters can undergo ester hydrolysis, which leads to rapid aging of flame-retardant flexible anode plates. Summary of the invention

[0006] In order to maximize the service life of the anode plate, this application provides a new yarn combination and fabric weaving method. The yarn is spun by optimizing the combination of non-flame retardant spun yarn and flame retardant spun yarn; and the fiber fabric is woven by adding bone yarn through a mixed weaving process. This fiber fabric is applied to the flexible anode plate, achieving the unity of high-efficiency flame retardancy and long-term mechanical stability of the flexible anode plate.

[0007] In order to achieve the above object, the technical solution of the present invention is:

[0008] In a first aspect, an industrial yarn is spun by plying and twisting industrial yarns made of conventional non-flame-retardant fiber materials and flame-retardant fiber materials with heat-resistant properties.

[0009] The conventional non-flame retardant fiber material is industrial polyester spun yarn.

[0010] The flame-retardant fiber material with heat resistance is preferably industrial nitrile chlorinated fiber yarn or industrial chlorinated fiber yarn. Nitrile chlorinated fiber is a modified acrylic fiber with high flame retardancy, acid resistance and chemical resistance, and its heat resistance temperature is about 100°C.

[0011] Furthermore, when the ambient temperature does not exceed 50°C, the flame-retardant fiber material is preferably chlorofiber. Industrial chlorofiber (polyvinyl chloride fiber) yarn is flame retardant and can be used for a long time below 50°C.

[0012] The industrial yarn is a short-fiber yarn, and a single short-fiber yarn is formed by plying a plurality of short-fiber spun yarns and twisting them.

[0013] The number of the multiple spun yarns is 2-10, wherein the ratio of the number of conventional industrial polyester spun yarns to the number of industrial acrylic spun yarns is in the range of 2:1-1:2.

[0014] Furthermore, the industrial polyester yarn and industrial nitrile yarn are both short-fiber yarns. The short filament fibers used in such short-fiber yarns have multiple breakpoints, which can form small water storage spaces and have good water retention capacity, which can effectively prevent the accumulation of surface charges on the fiber fabric plates during operation.

[0015] The industrial yarn is made by plying a plurality of spun yarns and twisting them, with a twist of 100-200 twists / m and an "S" type twisting. Twisting can give the yarn a certain structural form, certain physical and mechanical properties and appearance, and is beneficial to increasing the strength, elasticity, water retention capacity, etc. of the yarn.

[0016] The industrial polyester spun yarn is a conventional non-flame retardant spun yarn, does not contain phosphorus-based flame retardants, and has a diameter of 200D-500D (D, denier, a method of expressing the fineness of chemical fibers; its meaning is: the weight in grams of 9000 meters of yarn or fiber at the official regain, also known as denier).

[0017] The industrial nitrile chloroprene yarn does not contain phosphorus-based flame retardants, and its diameter can be characterized as 300-600D.

[0018] In the second aspect, a fiber fabric is woven from the above industrial yarn. During the weaving process, aramid is used as the skeleton and interlaced in the fabric, and the aramid skeleton has the function of enhancing the tensile strength of the fabric.

[0019] The fiber fabric has a plain weave structure or a twill weave structure or other combined pattern structures.

[0020] Furthermore, when the fiber fabric is twill woven, a 2 / 2-6 / 6 weaving method is adopted, preferably a 4 / 4 weaving method.

[0021] The aramid skeleton wires are intermittently mixed in the fabric, the aramid diameter can be characterized as 800-1200D, the width of the anode plate is 250-450mm, the height is 2-6m, the spacing of the warp aramid skeleton wires is 0.5-2cm, the spacing of the weft aramid skeleton wires is 0.3-1.5cm, and the skeleton wire density should correspond to the overall size of the anode plate used in the dust collector (including width and height): the larger the overall size of the anode plate, the greater the skeleton wire density.

[0022] Furthermore, the spacing of the warp aramid wires is greater than the spacing of the weft aramid wires, that is, the density of the aramid wires in the weft direction is greater than the density of the aramid wires in the warp direction. This is mainly because the horizontal tension on the flexible anode plate in the weft direction is greater than the vertical tension on the warp direction. It is necessary to set a greater wire density in the direction with greater force.

[0023] Due to the high cost of aramid, the mixed design can minimize the use of aramid and effectively reduce the cost of flexible anode plates.

[0024] Furthermore, the aramid fiber yarn is made by spinning filament yarn or short fiber yarn.

[0025] In a third aspect, a flexible anode plate of a wet electrostatic precipitator is made of the above-mentioned fiber fabric.

[0026] The beneficial effects of the present invention are:

[0027] 1. Industrial nylon yarn has natural flame retardant properties, and the limiting oxygen index can reach more than 37%. The industrial yarn / yarn required for the weaving of flexible anode plates is spun from industrial polyester yarn and industrial nylon yarn, which can not only ensure the mechanical strength of the plate but also maintain flame retardant properties.

[0028] 2. Due to the high strength and good chemical stability of aramid, it can be mixed into the fabric as a skeleton and effectively buffer the mechanical damage to the anode plate caused by thermal shrinkage of other fibers, smoke impact, etc.

[0029] 3. Due to the high cost of aramid, the mixed design can minimize the amount of aramid used and effectively reduce the cost of flexible anode plates. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The accompanying drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0031] Figure 1 Industrial yarn composition diagram provided for the examples;

[0032] Figure 2 A schematic diagram of the plain weave method and the mixed weave method of the skeleton wire of the flexible anode plate provided in the embodiment;

[0033] Among them, 1. industrial yarn, 2. conventional industrial polyester spun yarn, 3. industrial acrylic spun yarn, 4. aramid yarn, d1. the spacing of the warp aramid yarn, d2. the spacing of the weft aramid yarn. DETAILED DESCRIPTION

[0034] It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.

[0035] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0036] Example 1

[0037] (1) Spinning industrial yarn

[0038] The industrial yarn 1 is made of conventional non-flame-retardant fiber material and heat-resistant flame-retardant fiber material through plying and twisting. Figure 1 shown.

[0039] The conventional non-flame-retardant fiber material is industrial polyester spun yarn 2, which does not contain phosphorus-based flame retardants and has a diameter of 200D-500D.

[0040] The flame-retardant fiber material with heat-resistant effect is preferably industrial nitrile chlorofiber yarn 3 or industrial chlorofiber yarn, the composition does not contain phosphorus flame retardant, and the diameter can be characterized as 300-600D;

[0041] Acrylic chlorofiber is a modified acrylic fiber with high flame retardancy, acid resistance and chemical resistance, and its heat resistance temperature is about 100°C.

[0042] Furthermore, when the ambient temperature does not exceed 50°C, the flame retardant fiber material is preferably chlorofiber. Industrial chlorofiber (polyvinyl chloride fiber) yarn is flame retardant and can be used for a long time below 50°C.

[0043] Non-flame-retardant fiber materials and flame-retardant fiber materials are both short fiber yarns; the short silk fibers used in the short fiber yarns have multiple breakpoints and can form small water storage spaces; the manufactured yarns or fabrics have good water retention capacity and can effectively prevent the accumulation of surface charges on the fiber fabric plates during operation.

[0044] The industrial yarn 1 is a short-fiber yarn, and a single short-fiber yarn is made by plying and twisting a plurality of short-fiber spun yarns.

[0045] The number of yarns contained in a single industrial yarn 1 is 2-10, wherein the ratio of the number of conventional industrial polyester yarns 2 to the number of industrial acrylic yarns 3 is in the range of 2:1-1:2;

[0046] Preferably, a single industrial yarn 1 comprises 6 yarns, including 3 conventional industrial polyester yarns 2 and 3 industrial acrylic chlorofiber yarns 3, and the ratio of the number of conventional industrial polyester yarns 2 to the number of industrial acrylic chlorofiber yarns 3 is 1:1.

[0047] After a plurality of spun yarns are combined in a certain number and proportion, they are twisted to obtain industrial yarns with a twist of 100-200 twists / m and an "S" type twisting method; preferably, the twist is 150 twists / m.

[0048] (2) Woven fiber fabrics

[0049] The industrial yarn is woven into a fiber fabric through a weaving process and used as a material for making a flexible anode plate.

[0050] During the weaving process, aramid is used as the skeleton wire interval and mixed into the fabric. The aramid skeleton wire has the function of enhancing the tensile strength of the fabric. Due to the high cost of aramid, the mixed design can minimize the amount of aramid used and effectively reduce the cost of the flexible anode plate.

[0051] Aramid fiber yarn is made by spinning filament yarn or short fiber yarn, and its diameter can be characterized as 800-1200D.

[0052] The organizational structure of the fiber fabric is a plain woven structure or a twill woven structure or other combined pattern structures.

[0053] Furthermore, when the fiber fabric is twill woven, a 2 / 2-6 / 6 weaving method is adopted, and a 4 / 4 weaving method is preferably adopted.

[0054] When the fiber fabric adopts plain weave, the structure is as follows Figure 2 As shown, the industrial yarn 1 is mixed with the polyester skeleton yarn 4.

[0055] Since the horizontal tension on the latitude direction of the flexible anode plate is greater than the vertical tension on the warp direction, it is necessary to set a greater bone line density in the direction with greater force, that is: d1>d2.

[0056] In this embodiment, d1 is 0.5-2 cm, and d2 is 0.3-1.5 cm;

[0057] Preferably, when the anode plate used in the wet electrostatic precipitator has a width of 400 mm and a height of 4 m, d1 is 1.5 cm and d2 is 1.0 cm.

[0058] (3) Making a flexible anode plate

[0059] The above fiber fabric is processed into a flexible anode plate and applied to a wet electrostatic precipitator to treat wet saturated flue gas after wet desulfurization and reduce the content of acid droplets and fine particles in the flue gas. During operation, the flexible anode plate soaked in ionic liquid is placed in an acidic flue gas environment not exceeding 50°C, and the acid droplets and fine particles in the flue gas are captured on the flexible anode plate.

[0060] Long-term engineering practice shows that conventional industrial polyester and its fabrics are not flame retardant (limiting oxygen index is about 26%), which is related to their own properties; this scheme adopts the form of blending and co-weaving, combining the properties of the materials themselves (anti-aging property of polyester / flame retardancy of chlorofiber or acrylic chlorofiber / high strength of aramid), and uses a specific weaving method to make the manufactured flexible anode plate have both flame retardancy and anti-aging properties.

[0061] This solution does not change the dust removal mechanism of wet electrostatic dust removal, but mainly significantly improves the performance of traditional flame-retardant flexible fabric plates containing phosphorus-based flame-retardant ingredients. It eliminates the problem of ester hydrolysis and cleavage in actual environments, which seriously affects the performance of the plates. This solution completely solves this problem, and is lower in cost than using aramid completely. Compared with conventional industrial polyester yarns, it greatly increases the service life and makes the replacement cycle of flexible anode plates longer.

[0062] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A flexible anode plate made of fiber fabric, characterized in that: The flexible anode plate is a flexible anode plate of a wet electrostatic precipitator; The fiber fabric is woven from industrial yarns, using a mixed weaving process, using aramid as the skeleton thread interval mixed in the fabric; The aramid skeleton is made of filament yarn or short fiber yarn through spinning, and the diameter is characterized by 800-1200D. The spacing of the warp aramid skeleton is greater than the spacing of the weft aramid skeleton. The larger the overall size of the anode plate, the greater the density of the skeleton. The industrial yarn is spun by plying and twisting conventional non-flame-retardant fiber materials and heat-resistant flame-retardant fiber materials; The conventional non-flame-retardant fiber material is industrial polyester spun yarn; The flame-retardant fiber material with heat resistance is industrial nitrile chlorofiber yarn or industrial chlorofiber yarn; The industrial polyester spun yarn is a short fiber spun yarn, does not contain a phosphorus-based flame retardant, and has a diameter of 200D-500D; The industrial nitrile chlorinated yarn or industrial chlorinated chlorinated yarn is a short fiber yarn, does not contain a phosphorus-based flame retardant, and has a diameter of 300-600D; When the working temperature does not exceed 50℃, the flame retardant fiber material is industrial chloroprene yarn; A single industrial yarn is made by plying and twisting multiple short fiber yarns; The number of the plurality of short fiber yarns is 2-10, wherein the ratio of the number of industrial polyester yarns to the number of industrial acrylic yarns is in the range of 2:1-1:2; The number of the multiple short fiber yarns is 6, wherein the ratio of the number of industrial polyester yarns to the number of industrial acrylic yarns is 1:1; The twist is 100-200 twists / m, and the twisting method is "S" type twisting; The twist is 150 twists / m.

2. The flexible anode plate made of fiber fabric as claimed in claim 1, characterized in that: The fiber fabric has a plain weave structure, a twill weave structure, or other combined pattern structures; Furthermore, when the fiber fabric is twill woven, a 2 / 2-6 / 6 weaving method is adopted.

3. The flexible anode plate made of fiber fabric as claimed in claim 2, characterized in that: When the fiber fabric is twill woven, a 4 / 4 weaving method is adopted.

4. The flexible anode plate made of fiber fabric as claimed in claim 1, characterized in that: The spacing between the warp aramid bone wires is 0.5-2 cm, and the spacing between the weft aramid bone wires is 0.3-1.5 cm.

5. The flexible anode plate made of fiber fabric as claimed in claim 4, characterized in that: The spacing between the warp aramid bone wires is 1.5 cm, and the spacing between the weft aramid bone wires is 1.0 cm.

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